Sterilization and contraception increase lifespan across vertebrates

Area of Science:

• Evolutionary biology
• Gerontology
• Reproductive biology

Background:

• Reproduction is theorized to limit lifespan and cause sex-specific aging patterns.
• Sterilization and contraception methods' effects on survival vary by sex, hormones, and species.
• Understanding the link between reproduction and longevity is crucial for aging research.

Purpose of the Study:

• To investigate the impact of sterilization and contraception on lifespan across mammalian species.
• To analyze sex-specific differences in survival benefits from reproductive inhibition.
• To determine if these effects extend to other vertebrate groups and different environments.

Main Methods:

• Analysis of data from zoo and aquarium-housed mammals worldwide.
• Meta-analyses of published studies on sterilization and survival in vertebrates.
• Comparison of survival rates in gonadectomized rodents and castrated men.

Main Results:

• Hormonal contraception and surgical sterilization correlate with increased life expectancy in mammals.
• Survival benefits differ between sexes and are linked to specific causes of death.
• Sterilization improves survival across vertebrates, with enhanced healthspan in gonadectomized rodents.

Conclusions:

• The hormonal drive to reproduce constrains adult survival across vertebrate species.
• Reproductive inhibition, through various methods, generally enhances longevity.
• Findings suggest a conserved trade-off between reproduction and survival across the animal kingdom.